Tomalin-Reeves played all his rugby for Neath Port Talbot College and Aberavon Green Stars before being selected for daily training sessions with the C Group at the Ospreys alongside his full time job as a tree surgeon and gardener.
"I've thoroughly enjoyed stepping up to the Premiership this season. I'm taking this opportunity with both hands and I'm just pleased to have a chance to show what I've got," said Joe.
"I played all my club rugby at Aberavon Green Stars until now, and played for Neath Port Talbot College up until the start of this season. Both the club and the college helped me a lot, especially in preparing me for the step-up to Premiership rugby and training with the Ospreys, but the coaching I've received this season from my coaches at Swansea and the Ospreys has really taken me to the next level.
"My aim now is just to keep going in order to improve in training and in my games for Swansea, while making the Wales Under 20 squad next season is also now an objective."
Swansea assistant coach Damian Karauna said: "Joe has been outstanding in every way since joining us at the start of the season and his performances over the past six weeks in the League and Cup have been consistently impressive.
"For a player of his age, and with only a short time to train and develop physically at this level, to stand his own against some of the strongest packs in the Premiership is quite remarkable. His performance against Aberavon in particular had some of the most experienced forwards in the league patting him on the back at the end of the game."
Andrew Millward, Regional Performance Development Manager at the Ospreys, added: "We watched Joe played for his College at the end of last season and the start of this and we are really pleased with his progress, it just show that there are late developers out there within the club and college game who deserve every chance at making it in the elite game."
Joe Tomalin-Reeves Fact File
Education: St Joseph's School, Port Talbot, Neath Port Talbot College
Occupation: Tree Surgeon
Most Admired Rugby player: Richie McCaw